Roller cutter

ABSTRACT

A roller cutter assembly adapted to be fixed to the cutter head of a tunneling machine is disclosed. The cutter assembly includes a cutter rotatably mounted on a shaft so that end portions of the shaft project from the cutter. Each of those projecting end portions has a pair of flat faces the planes of which intersect at an angle of 90*. A generally U-shaped saddle having projecting arm portions mounts the shaft so that the cutter is rotatable on the shaft. Each arm of the saddle has a pair of flat faces the planes of which intersect at an angle of 90 degrees and which engage the faces on a projecting end portion of the shaft. The engaged faces are clamped together by bolts, each of which exerts a clamping force having components normal to the engaged faces and each of which is more nearly horizontal than vertical with respect to the intended cutting plane. According to one aspect of this invention, the cutter is a gauge cutter and one projecting arm portion of the saddle may be removed from the remainder of the saddle to facilitate removal and replacement of the gauge cutter.

United States Patent 11 1 1111 3,851,718 Fink Dec. 3, 1974 ROLLER CUTTER [57] ABSTRACT inventor: Trevor Fink, University Heights,

Ohio A roller cutter assembly adapted to be fixed to the cutter head of a tunneling machine is disclosed. The [73] Asslgnee: Solon Ohlo cutter assembly includes a cutter rotatably mounted [22] Filed: Aug. 20, 1973 on a shaft so that end portions of the shaft project from the cutter. Each of those projecting end portions [21] Appl has a pair of flat faces the planes of which intersect at R lated US. Application Data an angle of A generally U-shaped saddle having 3 cominuatiommpm f sen 30495 9 projecting arm portions mounts the shaft so that the 1972, abandoned, cutter is rotatable on the shaft. Each arm of the saddle has a pair of flat faces the planes of which intersect at 52 us. c1. 175/363, 175/364 an angle of 90 degrees ahd which engage the faces on 51 Int. Cl. E2lb 9/08, E21c 13/00 a p j g end portion Of the Shaft The engaged [58] Field Of Search .1 /334, 335, 344, 376, faces are clamped together y bolts each of which 125 357 3 1 3 3 3 4 3 74,7 299 erts a clamping force having components normal to 308/81 15 the engaged faces and each of which is more nearly horizontal than vertical with respect to the intended [56] Refere e Cited cutting plane. According to one aspect of this inven- UNITED STATES PATENTS tion, the cutter is a gauge cutter and one projecting 3 H6 513 11/1965 Robbins CI 3] /364 X arm portion of the saddle may be removed from the 'g [0/197] Dixon US$64 remainder of the saddle to facilitate removal and re- 3:705:635 12/1972 Conn 175/364 placement Ofthe gauge 3,749,188 7/1973 Schumacher..... 175/364 3,750,772 8/1973 Venter 1 175/364 3.79l,705 2/1974 Schimel 175/363 X Primary E.\'aminerDavid H. Brown Attorney, Agent, or FirmMcNenny, Farrington, Pearne & Gordon 15 Claims, 6 Drawing Figures mammal: 3w

SHEET 2 If 2 ROLLER CUTTER CROSS REFERENCE TO RELATED APPLICATION The present application is a continuation-in-part of my copending application Ser. No. 304,955, filed Nov. 9, 1972 entitled Roller Cutter and now abandoned.

BACKGROUND OF THE INVENTION This invention relates generally to tunneling machines, and more particularly to tunneling machines having a rotatable cutter head and roller cutters mounted on the cutter head for engaging an end face of a tunnel with rolling contact in one direction and for engaging the juncture between the end face and the wall of the tunnel with rolling contact in that one direc-- ports a .rotatable cutter head. Roller cutters are mounted on the cutter head, and rotation of the cutter head in one direction causes the cutters to travel about the end face of the tunnel with rolling contact to crush the formation encountered in a well known manner.

During the cutting operation, much of the rock' is crushed to a fine, extremely abrasive powder. Because of the presence of this powder, care must be taken to minimize the number of loose fitting connections between removable portions of the tunneling machine. Since portions of the tunneling machine must be removed for replacement, care must be taken to provide tight connections between such members so that the amount of abrasive material between mating surfaces will be minimized and movement between such members will also be minimized to prevent wear between the surfaces.

Since the cutter teeth will in time wear, the cutters must be replaced. Therefore, the shaft on which the cutter is rotatably mounted is removably mounted on the projecting arms of a U-shaped saddle. Typically, the shaft extends through bores in the saddle arms and is restrained against rotation and axial movement relative to the saddle by shaft lock screws or lock bolts which extend transversely through the bored arm and through one end of the shaft. Since no clamping force exits between the saddle and the shaft, precise tolerances must be maintained betweenthese members and between the saddle arm and the cross pin. To minimize wear between the saddle arm and the shaft, split bushings are normally provided to protect the load bearing area between the shaft and the saddle arm. This particular design has not been entirely successful in minimizing wear between the parts of the assembly. Furthermore, in order to replace a cutter, it is necessary to remove the cross pin and pull the shaft axially from the holes in the saddle arm, thus necessitating removal of the shaft from its cutter.

Other typical arrangements include saddle arms having projections which cradle the projecting shaft ends. In some of those arrangements, the cradle formed by the saddle arms is open-topped andeach shaft end is retained therein by a bolt which extends through the arms and through the shaft end. In others of those arrangements, the cradled shaft end is retained therein by one or more clamping members which cover or substantially cover the non-cradled portion of the shaft end between the saddle arms and which are bolted to at least one of the saddle arms. Although all of these arrangements permit removal of the cutter and its shaft as a unit from the saddle, certain problems exist. No significant clamping force obtains where the bolt extends through the arms and the shaft and the employment of one or more clamping members increases the interface area which may collect abrasive powder.

SUMMARY OF THE INVENTION The present invention overcomes these and other problems of prior art tunneling machines by providing a cutter assembly having an improved connection between the shaft and the saddle arms. According to the principles of the invention, the connection may be 'effected without maintaining precise tolerances between with one face being substantially normal to the lIl-' tended cutting plane. A generally U-shaped saddle having projecting arm portions mounts the shaft and has a face adapted to be secured to the cutter head. Each arm of the saddle has a pair of flat faces the planes of which intersect at an angle of 90 and which engage the faces on a projecting end portion of the shaft. The engaged faces are clamped together by bolts, each of which exerts a clamping force having components normal to the faces and each of which is more nearly hori-..

zontal than vertical with respect to the intended cutting plane and with respect to the mounting face of the saddle. A clamping bolt projects through each arm and through each end portion of the shaft at an angle so that force components force the faces into tight engagement, thus eliminating the maintenance of precise tolerances between those faces. Furthermore, if wear should occur between the mating faces, the bolt may be tightened to eliminate play and consequent abrasion between those faces. The orientation of the bolt is such that a larger force component obtains between the clamped faces which are substantially normal to the intended cutting plane, since greater magnitudes of load variation occur in directions substantially parallel to the intended cutting face.

According to one aspect of this invention, a gauge cutter is mounted in a similar assembly. However, in the case of a gauge cutter, removal of the cutter would normally be prevented by the tunnel wall. Therefore, according to this aspect of this invention, the saddle arm which is located radially inwardly of the tunnel 'wall is removable from the remainder of the saddle so that the cutter may be removed therefrom.

BRIEF DESCRIPTION OF THE DRAWINGS These and other aspects, principles, and advantages of this invention will become readily apparent to those skilled in the art upon a comprehensive understanding of the preferred embodiment of the invention shown in the accompanying drawings, wherein:

FIG. I is an elevational view of an inside cutter assembly according to the principles of the invention;

FIG. 2 is a right end view of the cutter assembly shown in FIG. 1;

FIG. 3 is a left end view of the cutter assembly illustrated in FIG. 1;

FIG. 4 is an elevational view of a gauge cutter assembly according to the principles of another aspect of this invention, showing the cutter in engagement with the juncture between a tunnel wall and face;

FIG. 5 is an end view of the assembly illustrated in FIG. 4, the plane of the view being indicated by the line 55 in FIG. 4', and

FIG. 6 is an end view of the assembly illustrated in FIG. 4, the plane of the view being indicated by the line 6-6 in FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings in greater detail, and

particularly to FIGS. 1 through 3, a cutter assembly 10 is illustrated. The assembly 10 includes a cutter ll roconventional bearings and bearing seals are provided between the shaft 12 and the cutter 11 to permit relative rotation between the cutter 11 and the shaft 12, while preventing abrasive grit from entering the bearing area.

Each of the projecting end portions of the shaft 12 has a pair of flat faces 14 and 15 which are angularly related to each other at an angle of 90. The projecting end portions are mounted on the ends of projecting arm portions 16 and 17 of a U-shaped saddle 18 so that the cutter 11 may rotate relative to the shaft. Each arm of the saddle 18 has a pair of flat faces 19 and 20 which are angularly related at an angle of 90 and which respectively engage the flat faces 14 and 15 of the shaft. For ease of machining, a fillet 21 may be provided between the faces 19 and 20 and the intersection of the faces 14 and 15 may be provided with a chamfer 22 so as not to interfere with the fillet 21.

Clamping means are provided at each end of the shaft to respectively clamp the faces 14 and 15 to the faces 19 and 20 of the projecting arms 16 and 17. According to this invention, the clamping means comprises bolts 23 and 24. The bolts 23 and 24 extend through the projecting ends of the shaft 12 and through the arms 16 and 17. Locking type nuts 25 and '26 are threaded onto the projecting ends of the bolts 23 and 24 and bear against bosses 27 and 28 on the arms 16 and 17.

It may be noted in FIGS. 2 and 3 that the bolts 23 and 24 are angularly related to the faces 14 and I9 and that an axial force F exerted by each bolt has components X and Y which are normal to and in the direction of the faces 19 and 20, thus securely clamping all of the mating faces together. This clamping force is sufficient to maintain a tight seal between the mating faces of the shaft and the arms of the U-shaped saddle to minimize the entry of grit between these surfaces. It should also be noted that any play between the mating surfaces may be taken up by a simple tightening of the bolts 23 and 24.

Each cutter assembly 10 is adapted to be driven in the direction of the arrows in FIGS. 2 and 3 as the cutter head (not shown) on which each cutter assembly 10 is mounted drives the assembly into the face 35 of the tunnel. During the cutting operation, there are substantially larger loads acting on the faces 15 and 20 than on the faces 14 and 19. However, those larger loads are substantially constant while greater magnitudes of load variations occur on the faces 14 and 19 because of variations in rock density and types encountered by the cutter in the rolling direction. Therefore, the bolts 23 and 24 are mounted so that they are more nearly horizontal than vertical with respect to the tunnel face 35 and a face 36 of the saddle 18 which is adapted to be secured to the cutter head. As a result of this mounting arrangement, the force component X exceeds the component Y to more effectively resist load variations on the faces 14 and 19, while the relatively small force component Y is added to by the relatively constant loads imposed normal to the face 36. i

To aid in locating the shaft 12 during installation, the arms 16 and 17 are provided with raised faces 29 which are parallel to the faces 19. The faces 29 do not exert any clamping pressure on the shaft 12, but may serve to retain the cutter in place if the bolts 23 or 24 should fail. Since the cutters are intended to be rotated only in the single indicated direction, a clamping force need not be applied by the saddle 18 to the face of the shaft 12 opposite the face 14 and this permits clear access to the heads of the bolts 23 and 24 for replacement of the cutter.

A plurality of inside cutter assemblies 10 are located in predetermined positions on the forward end face of the cutter head (not shown) by locating dowel pins (not shown) which project from the face of the cutter head and which enter dowel pin openings 30 in the bottom face 36 of the saddle 18. After the saddles are located on the cutter head in this manner, the saddles are welded to the face of the cutter head.

Referring now to FIGS. 4 through 6, a gauge roller cutter assembly according to a further aspect of this invention is illustrated. The assembly 50 includes a cutter 51 rotatably mounted on a shaft 52 so that end portionsof the shaft project from the cutter. The cutter is provided with circumferential discs 53 which are similar to the discs 13 illustrated in FIGS. 1 through 3. Each projecting end portion of the shaft 52 is provided with flat faces 54 and 55 which are angularly related at an angle of 90 degrees, and those end portions are mounted on projecting arms 56 and 57 of a U-shaped saddle 58. The arms 56 and 57 are provided with flat faces 59 and 60, which are angularly related to an angle of 90 degrees and which respectively mate with the faces 54 and 55 on the ends of the shaft 52. A tillet 61 is provided at the intersection of the faces 59 and and a chamfer 62 is provided at the intersection of the faces 54 and 55 to clear the fillet 61.

Clamping means are provided at each end of the shaft to respectively clamp the faces 54 and 55 to the faces 59 and 60 of the projecting arms 56 and 57. Ac-

cording to this invention, the clamping means comprises bolts 63 and 64. The bolts 63 and 64 extend through the projecting ends of the shaft 52 and through the arms 56 and 57. Locking type nuts 65 and 66 are threaded onto the projecting ends of the bolts 63 and 64.

lt may be noted in FIGS. 5 and 6 that the bolts 63 and 64 are angularly related to the faces 54 and 59 and that an axial force F exerted by each bolt has components X and Y which are normal to and in the direction of the faces 59 and 60, thus securely clamping all of the mating faces together. This clamping force is sufficient to maintain a tight seal between the mating faces of the shaft and the arms of the U-shaped saddle to minimize the entry of gut between the surfaces. It should also be noted that any play between the mating surfaces may be taken up by a simple tightening of the bolts 63 and 64.

To aid in locating the shaft 52 during installation, the arms 56 and 57 are provided with raised faces 70 which are parallel to the faces 59. The faces 70 also serve to retain the shaft 52 during cutting operations, but it should 'be noted that the faces 70 do not exert any clamping pressure on the shaft 52.

A plurality of gauge cutter assemblies 50 are located in predetermined positions on the outer rim of the forward end face of a cutter head (not shown) by locating dowel pins (not shown) which project from the face of the cutter head and which enter dowel pin openings 71 in the bottom face of the saddle 58. After the saddles are located on the cutter head in this manner, the saddles are welded to the face of the cutter head. The predetermined positions of the gauge cutters are adjacent the periphery of the cutter head since they are intended to operate in the angular juncture of the face and walls of the tunnel. Furthermore, the saddle 58 supports the shaft 52 in such a manner that the axis of rotation of the gauge cutter is at an angle to the axis of rotation of the inside cutters.

To replace the cutter 51, the tunneling machine is backed from the face 72 of the tunnel to allow access. However, since one end of the cutter 51 remains in contact with the tunnel wall 73, it will be noted that the cutter 51 may not -be removed from the saddle 58 merely by removing the bolts 63 and 64, since in such a situation, the cutters must be moved in a direction parallel to faces 78 of the cutter'Sl to permit the shaft to clear the faces 70. Therefore, means are provided to permit removal of the cutter 51 in a direction parallel to the wall 73. As may be seen most clearly in FIGS. 4 and 5, this removal means includes a removable portion 74 of the arm 56. The portion 74 is fixed to the remainder of the arm 56 by bolts 75 and by a projecting key portion 76 of theportion 74 which enters a key slot 77 in the remainder of the arm 56. Thus, the cutter 51 maybe removed from the saddle-58 by removing the bolts 75 and the bolts 64 and removing the assembly in a direction parallel to'the wall 73. It should be noted that the bolt 63 need not be removed to perform this operation.

While I have described my invention in connection with specific embodiments thereof, it is to be clearly understood that this is done only by way of example, and not as a limitation to the scope of my invention as set forth in the objects thereof and in the appended claims.

What is claimed is:

l. A roller cutter assembly comprising a cutter rotatably mounted on a shaft so that end portions of said shaft project from said cutter. said end portions having first and second flat angularly related faces. a generally U-shaped saddle having projecting arm portions mounting said shaft and a mounting face adapted to be secured to a cutter head, each projecting arm portion having first and second flat angularly related faces respectively engaging the first and second faces on each said end portion, means for clamping each arm to each end portion and for providing a clamping force between engaged faces having components normal to each face, said clamping means providing a greater force component parallel to said mounting face.

2. A roller cutter assembly according to claim 1, wherein non-engaged portions of said projecting arm portions are substantially exposed to allow clear access to said clamping means.

3. A roller cutter according to claim 1, wherein one of said projecting arms has means removably fixing it to the remainder of said U-shaped saddle.

4. A roller cutter assembly according to claim 1, wherein the planes of said angularly related faces define an'angle of about 5. A roller cutter assembly according to claim 4, wherein said first and second faces intersect.

6. A roller cutter assembly according to claim 1, wherein said means for clamping comprises a bolt extending through each end portion and at least one of said faces on said arm portion.

7. A roller cutter assembly according to claim 6, wherein said bolts are more nearly horizontal than vertical with respect to said mounting face.

8. An inside roller cutter assembly adapted to be fixed to a rotatable cutter head, comprising a cutter ro tatably mounted on a shaft so that end portions of said shaft project from said cutter, said end portions having first and second flat faces intersecting at an angle of about 90 degrees, a generally U-shaped saddle having projecting arm portions mounting said shaft and a mounting face adapted to be secured to a cutter head, each projecting arm portion having first and second flat faces intersecting at an angle of about 90 degrees, and respectively engaging the first and second faces on each said end portion, a bolt extending through each end portion and at least one of said faces on said arm portion, each bolt defining an acute angle with said at least one of said faces and clamping said first and second faces of said end portion to the first and second faces of said, arm portion with a force having components normal to each face, each bolt being more nearly horizontal than vertical with respect to said mounting face.

9. An inside roller cutter assembly according to claim 8, wherein non-engaged portions of said projecting arm portions are substantially exposed to allow clear access to said clamping means.

10. A gauge roller cutter assembly adaptedto be fixed to a rotatable cutter head, comprising a cutter rotatably mounted on a shaft so that end portions of said shaft project from said cutter, said end portions having first and second flat faces intersecting at an angle of about 90, a generally U-shaped saddle having projecting arm portions mounting said shaft and a mounting face adapted to be secured to a cutter head, each projecting arm portion having first and second flat faces intersecting at an angle of about 90 degrees and respectively engaging the first and second faces on each said end portion, one of said arm portions having means removably fixing it to the remainder of said U-shaped saddle, a bolt extending through each end portion and at least one of said faces on said arm portion, each bolt defining an acute angle with said at least one of said faces and clamping said first and second faces of said end portion to the first and second faces of said arm portion with a force having components normal to each face, each bolt being more nearly horizontal than vertical with respect to said mounting face.

11. A gauge roller cutter assembly according to claim 10, wherein said means removably fixing one of said arm portions includes bolt means.

12. A gauge roller cutter assembly according to claim 11, wherein said means removably fixing one of said arm portions includes a key projecting from said one of said arm portions and a cooperating 'slot on said remainder of said U-shaped saddle.

13. A gauge roller cutter assembly adapted to be fixed to a rotatable cutter head, comprising a cutter rotatably mounted on a shaft so that end portions of said shaft project from said cutter, said end portions having first and second flat faces intersecting at an angle of about 90, a generally U-shaped saddle having projecting arm portions mounting said shaft and a mounting face adapted to be secured to a cutter head, each projecting arm portion having first and second flat faces intersecting at an angle of about and respectively engaging the first and second faces on each said end portion, one of said arm portions having means removably fixing it to the remainder of said U-shaped saddle, a bolt extending through each end portion and at least one of said faces on said arm portion, each bolt being more nearly horizontal than vertical with respect to said mounting face defining an acute angle with said at least one of said faces and clamping said first and second faces of said end portion to the first and second faces of said arm portion with a force having components normal to each face.

14. A gauge roller cutter assembly according to claim 13, wherein said means removably fixing one of said arm portions includes bolt means.

15. A gauge roller cutter assembly according to claim 14, wherein said means removably fixing one of said arm portions includes a key projecting from said one of said arm portions and a cooperating slot on said remainder of said U-shaped saddle. 

1. A roller cutter assembly comprising a cutter rotatably mounted on a shaft so that end portions of said shaft project from said cutter, said end portions having first and second flat angularly related faces, a generally U-shaped saddle having projecting arm portions mounting said shaft and a mounting face adapted to be secured to a cutter head, each projecting arm portion having first and second flat angularly related faces respectively engaging the first and second faces on each said end portion, means for clamping each arm to each end portion and for providing a clamping force between engaged faces having components normal to each face, said clamping means providing a greater force component parallel to said mounting face.
 2. A roller cutter assembly according to claim 1, wherein non-engaged portions of said projecting arm portions are substantially exposed to allow clear access to said clamping means.
 3. A roller cutter according to claim 1, wherein one of said projecting arms has means removably fixing it to the remainder of said U-shaped saddle.
 4. A roller cutter assembly according to claim 1, wherein the planes of said angularly related faces define an angle of about 90*.
 5. A roller cutter assembly according to claim 4, wherein said first and second faces intersect.
 6. A roller cutter assembly accordIng to claim 1, wherein said means for clamping comprises a bolt extending through each end portion and at least one of said faces on said arm portion.
 7. A roller cutter assembly according to claim 6, wherein said bolts are more nearly horizontal than vertical with respect to said mounting face.
 8. An inside roller cutter assembly adapted to be fixed to a rotatable cutter head, comprising a cutter rotatably mounted on a shaft so that end portions of said shaft project from said cutter, said end portions having first and second flat faces intersecting at an angle of about 90 degrees, a generally U-shaped saddle having projecting arm portions mounting said shaft and a mounting face adapted to be secured to a cutter head, each projecting arm portion having first and second flat faces intersecting at an angle of about 90 degrees, and respectively engaging the first and second faces on each said end portion, a bolt extending through each end portion and at least one of said faces on said arm portion, each bolt defining an acute angle with said at least one of said faces and clamping said first and second faces of said end portion to the first and second faces of said arm portion with a force having components normal to each face, each bolt being more nearly horizontal than vertical with respect to said mounting face.
 9. An inside roller cutter assembly according to claim 8, wherein non-engaged portions of said projecting arm portions are substantially exposed to allow clear access to said clamping means.
 10. A gauge roller cutter assembly adapted to be fixed to a rotatable cutter head, comprising a cutter rotatably mounted on a shaft so that end portions of said shaft project from said cutter, said end portions having first and second flat faces intersecting at an angle of about 90*, a generally U-shaped saddle having projecting arm portions mounting said shaft and a mounting face adapted to be secured to a cutter head, each projecting arm portion having first and second flat faces intersecting at an angle of about 90 degrees and respectively engaging the first and second faces on each said end portion, one of said arm portions having means removably fixing it to the remainder of said U-shaped saddle, a bolt extending through each end portion and at least one of said faces on said arm portion, each bolt defining an acute angle with said at least one of said faces and clamping said first and second faces of said end portion to the first and second faces of said arm portion with a force having components normal to each face, each bolt being more nearly horizontal than vertical with respect to said mounting face.
 11. A gauge roller cutter assembly according to claim 10, wherein said means removably fixing one of said arm portions includes bolt means.
 12. A gauge roller cutter assembly according to claim 11, wherein said means removably fixing one of said arm portions includes a key projecting from said one of said arm portions and a cooperating slot on said remainder of said U-shaped saddle.
 13. A gauge roller cutter assembly adapted to be fixed to a rotatable cutter head, comprising a cutter rotatably mounted on a shaft so that end portions of said shaft project from said cutter, said end portions having first and second flat faces intersecting at an angle of about 90*, a generally U-shaped saddle having projecting arm portions mounting said shaft and a mounting face adapted to be secured to a cutter head, each projecting arm portion having first and second flat faces intersecting at an angle of about 90* and respectively engaging the first and second faces on each said end portion, one of said arm portions having means removably fixing it to the remainder of said U-shaped saddle, a bolt extending through each end portion and at least one of said faces on said arm portion, each bolt being more nearly horizontal than vertical with respect to said mounting face defining an acute angle with said at least one of said faces And clamping said first and second faces of said end portion to the first and second faces of said arm portion with a force having components normal to each face.
 14. A gauge roller cutter assembly according to claim 13, wherein said means removably fixing one of said arm portions includes bolt means.
 15. A gauge roller cutter assembly according to claim 14, wherein said means removably fixing one of said arm portions includes a key projecting from said one of said arm portions and a cooperating slot on said remainder of said U-shaped saddle. 